Heat exchanger



Oct. 27, 1953 c. s.' slMPELAAR HEAT EXCHANGER 2 Sheets-Sheet l Filed Dec. 6, 1948 fave/2757 C ZV1/cie 5.' Sippe/aar 4% M OGL 27, 1953 c. s, SIMPELAAR 2,657,018

HEAT EXCHANGER Filed Dec. 6, 1948 2 Sheets-Sheet 2 with the air inlet 3 through a passageway 9 located adjacent the bottom of the exchanger 4. The ducts and 6 are merged into a common outlet I I by an outer` wall I2. Positioned in the body portion 2 and interposed between the inlet side of the heat exchanger 4 and the inlet 3 is a motor I3 operable to drive a fan I4 in the proper direction to force air through the heat exchanger 4, duct 6, and outlet Il, the amount of air flowing through the exchanger 4 and passageway 9 being dependent upon the position of the respective dampers 'l and 8 in the ducts 5 and 6.

In the construction illustrated in Fig. 1, the motor I3 is mounted on a bracket I5 carried by the heat exchanger 4, the latter` being operatively connected to a fluid supply line IE and return line I'I of the cooling system of the vehicle to which the heater is applied.

Referring to Figs. 2 to 5 inclusive, which illustrate the details of construction of the heat exchanger 4 illustrated in Fig. 1, 2l represents a centrally located header having chambers 22 and 23 respectively designated for the purposes of describing the inlet and outlet chambers. The chamber 22 is provided with a fluid inlet 24, and the chamber 23 with a fluid outlet 25 adapted to be connected to the supply line I6 and return line I'I. The respective iiuid inlets and outlets are operatively connected to the header 2l by tu.-

bular members 26 and 27 respectively, which are secured to the end walls 28 of the heater, the end walls 28 and partition wall 29 dividing the header 2l into the chambers 22 and 23 being secured to the outer wall 3l of the heater by any suitable means, such as soldering or the like. As

illustrated in Figs. 2 and 6, the outer wall 3l of the header 2l is composed of a spirally shaped portion 3m and a radial portion 3|b, the latter extending from the end of the spiral portion 33 having the smallest radius to the adjacent end of the wall having the longest radius.

As shown in Figs, 5 and 6, the liquid pass in the construction illustrated is constructed from a pair of sheets 32 and 33 substantially equally spaced through their length and secured to one another adjacent their longitudinal edges 34 and 35 and end edges 36 to form a iluid tight joint therebetween. In the construction illustrated, the edges 34, 35, 33 of the respective sheets are pre-formed, as indicated at 31, and seam Welded to provide a fluid tight joint. The sheet 32 is secured to the spirally shaped portion Sla. opposite the free end of the radial portion 31h, and the sheet 33 to the outer edge of the radial portion 3Ib of the header wall 3| by any suitable means and, in a preferred form of the invention, the header wall 3l and sheets 32 and 33 may be constructed from a single piece of material formed to the desired shape. The sheets 32 and 33 are each provided with longitudinally extending inset portions or ribs 38 and 39, and 38 and 39' respectively, the ribs 33 and 39 on the sheet 32 being oppositely disposed with respect to the corresponding ribs 38 and 39 on the sheet 33 with the opposed ribs being seam welded or otherwise secured together t0 form partitions dividing the space between the sheets 32 and 33 into a series of longitudinally extending tubular channels 40 and 40. As illustrated in Fig. 5, the ribs 33 formed terminate short oi the end 3B whereby the respective pairs of channels 43 and 43 adjacent such end are operatively connected, while the ribs 39 extend to such end. In similar manner the ribs 33 extend to the juncture of the sheets 32 and 33 with the header 2l, whilethe i ribs 33 terminate short thereof whereby the channels 43 are operatively connected thereat. Extending between the ends of the respective pairs of ribs 33 and 38 adjacent the header 2l, is a transverse indentation or rib 4I which is bonded to the radial portion Sib of the header, thus sealing the adjacent end of the 4sheets 32 and 33 between the ribs 38 and 33 and providing a tortuous iiuid pass between the inlet chamber 22 and the outlet chambei` 23, the fluid consecutively passing through the channels 4U and 4U as indicated by the broken arrows in Fig. 5.

It will be apparent that, while I have illustrated the partitions as being formed by cooperating indentations or ribs in the respective sheets 32 and 33, secured together by seam welding or the like, the partitions may be formed by any suitable means as, for example, interposing desired lengths of flat wire or the like between the two sheets and suitably bonding such wires to the respective sheets.

The fluid pass thus formed is shaped into the form of a spiral, as clearly illustrated in Fig. 2, that portion of the sheets 32 and 33 adjacent the end 33 being curved on the longest radius with the convolutions oi the spiral being substantially equally spaced and forming the pass for the air, gas, or other fluid. Positioned in the space thus formed between the various convolutions of the uid pass are a plurality of fin elements 22 illustrated in the present instance as being formed by a continuously corrugated strip Q3, as shown in Fig. fl, with the connecting portions at alternating ends of the respective iins being bonded to the sheets 32 and 33, and function to conduct heat from the sheets 32 and 33 to the air or other luid owing through the iinned pass therebetween. While I have illustrated the n elements as being formed from a corrugated strip, any other suitable type of iin may be employed.

As illustrated in Fig. 2, the fins 42 extend throughout the length of the sheets 32 and 33 with the outer convolution of ins being enclosed by a curved outer wall 41% and an offset wall 45 adjacent the end 35 of the fluid pass. If an air by-pass is desired, a wall 43 may be provided whereby the outer wall of the exchanger is substantially circular to provide a by-pass passage 9, and if no 'oy-pass is desired, the substantially circular cross section of the exchanger may be maintained by employing the wall 46 and closing the passage 3 by a suitable baiile member.

In some instances it may be desirable to employ a single or straight iluid pass as contrasted with the tortuous path formed by the partition ribs 38, 33 and 39, 39 whereby the uid ilows through the device in a single direction. In such construction the header 2l may constitute merely the inlet or outlet header, with a second header being provided adjacent the end 33 of the sheets 32 and 33. Such a construction is illustrated in Fig.v 7 wherein the end 33 of the sheets 32 and 33 are left open and connected to a second header 2l. In such construction the partition 29 of the header 2l would be omitted, together with the sealing bead tl, and a solid end wall substituted for one of the walls 28. Likewise, the partition ribs 38, 33 and 3i), 33 could be omitted, 0r if desired, could be employed to reinforce the duid pass, all fluid, however, flowing directly from the header ZI to the header 2 l If desired, a by-pass corresponding to the by-pass 9 may be provided, or the generally circular shape of the exchanger may be completed by the wall 46 and a suitable baille employed to close the space 9. The latter, however, in this construction will be of slightly less area than the passage 9 illustrated in Fig. 2.

In fabricating theexchanger, the tube or liquid pass and the iin elements are assembled in the spiral manner shown. If the tube or tubes are pre-formed, they are wound into a slightly closer spiral than the nal form andV sprung openillke a spring to` admit the iin elements. This` spring action tends to give good Contact between the elements and the tubes and to assist in compacting the structure during the bonding operation. However, if tube is formed in the flat and wrapped around the centrali manifold; with the fins, it may be drawn tightly into position by a band or casing held in tension, the band or casing, if desired, being bonded around the periphery at the time the assembly is bonded. If this band is omitted, the structure may be clamped by the bonding device.

It will be noted that, with the present construction as applied in a heater such as that illustrated in Fig. l employing a fan, the header 2l taking the place of the usual single inlet and single outlet headers is positioned on substantially the axis of the fan; consequently, the header is located at the minimum air now produced by the fan, whereas in conventional types of construction the headers are adjacent the periphery of the air iiow, which is normally that of maximum iow. It will also be apparent that with the present construction the headers not only serve as distribution plenums, but also as heat transfer surface, substantially all of the header surface being exposed to the air flow.

Having thus described my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of my invention: hence, I do not wish to be understood as limiting myself to the exact form, construction, arrangement, and combination of parts herein shown and described or uses mentioned.

What I claim as new and Letters Patent is:

l. The combination with a heat exchange device including a tubular housing, of a heat exchanger mounted in said housing and comprising in combination a double walled tube formed from spaced plates and provided with laterally arranged interconnected passes and formed into a spiral formation, providing a fluid pass of spiral formation having an inlet end and an outlet end, a substantially centrally located header having a cross partition therein dividing the header into an inlet chamber and an outlet chamber, operatively com'municating respectively with the inlet and outlet ends of said pass, the convolutions of the tube being spaced apart to leave a second spiral iiuid pass between the convolutions, fln elements extending across the last mentioned pass between the convolutions and bonded to the walls of the first mentioned pass, said tubular housing also forming a by-pass passage contiguous to the outer end of the second spiral fluid pass, and damper means operatively mounted on said tubular housing contiguous to the heat exchange device for controlling the ow of a second fluid through said tubular housing.

2. A substantially cylindrically shaped heat exchanger adapted for operatively mounting Within a tubular housing of the heat exchanger and comprising in combination walls providing a double walled flattened tube providing a uid desire to secure by passage of spiral formation, having an inlet` end and an outlet end, said flattened tube being di, vided bypartitionsinto a tortuous pass, some of the partitions terminating short of the outer end ofl the outermost convolution, and some termia hating short or the end of the innermost com volution, whereby a tortuous pass is. provided. from the inlet. end to the outlet end: and a substane tially centrally located header having an inilet chamber-and outlet chamber communicating respectively with the inlet and outlet endsv of the pass, said convolutions being spaced apart to leave a second spiral pass for a second fiuid, iin elementsV extending from the inlet end to the outlet end and across said second pass and bonded to the walls of the tube, and a by-pass passage formed by said tubular housing and the outer end of the second spiral pass.

3. In a heat exchange` device including a, heat exchangerl and a. tubularhousing therefor, the combination of a substantially centrally located header, a double Walled substantially hat and elongated tubular member having an inlet opening therein at one end and an outlet opening therein at the other end, said tubular member being secured at one end to said header and having one of said openings communicating with said header, said elongated tubular member being spirally curved around said header with the convolutions of said member being spaced from one another, iin means positioned in the spaces between said convolutions, a second header connected to the other end of said tubular member and operatively communicating with the other opening therein, said heat exchanger formed With the tubular member including outlet pas sages, said second header, tubular member and periphery of the tubular member contiguous to the second header form a by-pass passage, and damper means operatively mounted within the outlet passages of the tubular member operatively connected to the passage formed by the spaced convolutions and the by-pass passage for controlling the iioW of the fluids lthrough said tubular member.

4. The combination with a heat exchange device including a tubular housing and :duid air circulating means mounted therein, of a heat exchanger dividing the tubular housing into an air inlet chamber and an air outlet chamber and comprising in combination a centrally located header, having an inlet chamber and an outlet chamber, a double walled tube of spiral formation having an inlet and an outlet end and providing a. pass for a heat exchange fluid, the convolutions of said spiral tube being spaced apart to provide a pass for a second iiuid and iin elements extending across second named pass and bonded to the Walls of the tube, said heat exchanger also forms With said tubular housing a. by-pass passage at the outlet end of said passl for the second iiuid, said heat exchanger forms with the housing of the air outlet chamber air mixing means including more than one duct, one of said ducts connected to said second named pass and the other of said ducts connected to the by-pass passage on the downstream side of the heat exchanger, and damper means for each of said ducts for controlling the flow of the: fluids through the air mixing means.

5. The combination with a heat exchange device including a tubular housing, of a heat exchanger mounted in said housing and dividing the tubular housing into an air inlet chamber and an air outlet chamber, said heat exchanger comprising in combination a substantially centrally located header having an air inlet chamber and an air outlet chamber, a double Wall flattened tube of spiral formation having an inlet end and an. outlet end and having a tortuous pass from end to end, for a heat exchanging fluid, the convolutions of said spiral tube being spaced apart to provide a pass for a second fluid, iin elements extending across said second named pass and bonded to the walls of the tube, a bypass passage formed by said tubular housing and the outer end of said second named pass, said air outlet chamber on the downstream side of the heat exchanger formed into a plurality of ducts operatively connected to said heat exchanger, one of said ducts operatively connected to the second named pass and the other of said; ducts operatively connected to the by-pass passage, and damper means in each of said ducts for controlling and proportioning the iiow of the fluids through said ducts within saidtubular housing.

CLYDE S. SIMPELAAR.

References Cited in the file of this patent UNITED STATES PATENTS 

